HRDI.Ii'KA] 



PHYSICAL ANTHROPOLOGY 



277 



tested on our splendid material from St. Lawrence Island. Taking 

 the broadest and the narrowest skulls from this locality, the follow- 

 ing data are obtained for the proportions of the upper dental arch: 



Eskimo Crania: Dental Arch and Form of Skull 

 st. lawrence island material 



The above figures show several conditions. The first is that the 

 arch is quite distinctly larger in the narrow than in the broad skulls 

 in both sexes. The second fact is that the skull (vault) itself is 

 slightly larger in the narrow-headed. The third is that the length of 

 the arch is somewhat greater in the narrow and long skulls than it is 

 in the broad ami shorter, relatively to the skull size. The fourth is 

 that there appears a close correlation, more particularly in the 

 females, between the length of the arch and that of the skull. 



THE I4ASI0N-NASI0N DIAMETER 



The anterior basal length (basion-nasion) is a measurement of 

 importance, though its full meaning in anthropology is not yet 

 entirely clear. From data quoted by Martin (Lehrb., 715-716) it 

 appears to average in whites up to 10.3 centimeters in males and up 

 to 10.1 centimeters in females, and is known to correlate closely with 

 the length of the vault. Secondarily it also correlates with stature. 



Data on American Indians are not yet generally available, though 

 in preparation. The Munsee skulls gave the writer for the diameter 

 the means of L0.27 for the males and 10.02 for the females; the 

 mound skulls from Arkansas and Louisiana gave 10.45 for the males 

 and 9.77 for the females. 



